Los Angeles Reservoir is Safe From Earthquakes

Abstract: The Los Angeles Reservoir was nominated for the 1978 Outstanding Civil Engineering Achievement Award. The reservoir, which replaces the Van Norman Reservoir damaged during the 1971 San Fernando earthquake, provides regulatory and emergency storage for water supply. To ensure the dam's safety during severe earthquakes, it was designed using a dynamic finite element program; dynamic triaxial shear strength tests were used to evaluate dynamic soil properties. The dam is a compacted earth fill with flat (3.5:1 and 3:1) slopes. It includes an internal vertical gravel drain to intercept water seeping through the dam. Seepage is conveyed to a gravel drainage blanket at the foundation, then to the toe of the dam. The cross-section also includes a plastic clay zone and a cobble zone at the base of the vertical drain.